function Person(name,age){
    this.name = name;
    this.age = age;
    this.run = function(){
        console.log("run")
    }
}
//大写开头定义构造函数
let obj = new Person("heloo",18)
//this一定要清楚，this代表什么，谁调用，就是谁
console.log(obj.name)
